The simplify part: do not touch pi_desc.nv, we can set it when the
VCPU is first created. Likewise, pi_desc.sn is only handled by
vmx_vcpu_pi_load, do not touch it in __pi_post_block.
The fix part: do not check kvm_arch_has_assigned_device, instead
check the SN bit to figure out whether vmx_vcpu_pi_put ran before.
This matches what the previous patch did in pi_post_block.
Cc: Huangweidong <weidong.huang@huawei.com>
Cc: Gonglei <arei.gonglei@huawei.com>
Cc: wangxin <wangxinxin.wang@huawei.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Tested-by: Longpeng (Mike) <longpeng2@huawei.com>
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
In some cases, for example involving hot-unplug of assigned
devices, pi_post_block can forget to remove the vCPU from the
blocked_vcpu_list. When this happens, the next call to
pi_pre_block corrupts the list.
Fix this in two ways. First, check vcpu->pre_pcpu in pi_pre_block
and WARN instead of adding the element twice in the list. Second,
always do the list removal in pi_post_block if vcpu->pre_pcpu is
set (not -1).
The new code keeps interrupts disabled for the whole duration of
pi_pre_block/pi_post_block. This is not strictly necessary, but
easier to follow. For the same reason, PI.ON is checked only
after the cmpxchg, and to handle it we just call the post-block
code. This removes duplication of the list removal code.
Cc: Huangweidong <weidong.huang@huawei.com>
Cc: Gonglei <arei.gonglei@huawei.com>
Cc: wangxin <wangxinxin.wang@huawei.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Tested-by: Longpeng (Mike) <longpeng2@huawei.com>
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
When the kernel is entered at EL2 on an ARMv8.0 system, we construct
the EL1 pstate and make sure this uses the the EL1 stack pointer
(we perform an exception return to EL1h).
But if the kernel is either entered at EL1 or stays at EL2 (because
we're on a VHE-capable system), we fail to set SPsel, and use whatever
stack selection the higher exception level has choosen for us.
Let's not take any chance, and make sure that SPsel is set to one
before we decide the mode we're going to run in.
Cc: <stable@vger.kernel.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Eric has reported that since commit d2faa41516 "quota: Do not acquire
dqio_sem for dquot overwrites in v2 format" test generic/232
occasionally fails due to quota information being incorrect. Indeed that
commit was too eager to remove dqio_sem completely from the path that
just overwrites quota structure with updated information. Although that
is innocent on its own, another process that inserts new quota structure
to the same block can perform read-modify-write cycle of that block thus
effectively discarding quota information update if they race in a wrong
way.
Fix the problem by acquiring dqio_sem for reading for overwrites of
quota structure. Note that it *is* possible to completely avoid taking
dqio_sem in the overwrite path however that will require modifying path
inserting / deleting quota structures to avoid RMW cycles of the full
block and for now it is not clear whether it is worth the hassle.
Fixes: d2faa41516
Reported-and-tested-by: Eric Whitney <enwlinux@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
My Fujitsu-Siemens Lifebook S6120 doesn't have the FUJ02E3 device,
but it does have FUJ02B1. That means we do register the backlight
device (and it even seems to work), but the code will oops as soon
as we try to set the backlight brightness because it's trying to
call call_fext_func() with a NULL device. Let's just skip those
function calls when the FUJ02E3 device is not present.
Cc: Jonathan Woithe <jwoithe@just42.net>
Cc: Andy Shevchenko <andy@infradead.org>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: <stable@vger.kernel.org> # 4.13.x
Signed-off-by: Darren Hart (VMware) <dvhart@infradead.org>
In generic_file_llseek_size, return -ENXIO for negative offsets as well
as offsets beyond EOF. This affects filesystems which don't implement
SEEK_HOLE / SEEK_DATA internally, possibly because they don't support
holes.
Fixes xfstest generic/448.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
In commit fd26a88093 we added a worst case estimate for rmapbt blocks
needed to satisfy the block mapping request. Since then, we added the
ability to reserve enough space in each AG such that we should never run
out of blocks to grow the rmapbt, which makes this calculation
unnecessary. Revert the commit because it makes the extra delalloc
indlen accounting unnecessary and incorrect.
Reported-by: Eryu Guan <eguan@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
My previous patch: d3a304b629 check for
XFS_LI_FAILED flag xfs_iflush done, so the failed item can be properly
resubmitted.
In the loop scanning other inodes being completed, it should check the
current item for the XFS_LI_FAILED, and not the initial one.
The state of the initial inode is checked after the loop ends
Kudos to Eric for catching this.
Signed-off-by: Carlos Maiolino <cmaiolino@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
We call __xfs_ag_resv_init to make a per-AG reservation for each AG.
This makes the reservation per-AG, not per-filesystem. Therefore, it
is incorrect to adjust m_ag_max_usable for each AG. Adjust it only
when we're reserving AG 0's blocks so that we only do it once per fs.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Since commit d531d91d69 ("xfs: always use unwritten extents for
direct I/O writes"), we start allocating unwritten extents for all
direct writes to allow appending aio in XFS.
But for dio writes that could extend file size we update the in-core
inode size first, then convert the unwritten extents to real
allocations at dio completion time in xfs_dio_write_end_io(). Thus a
racing direct read could see the new i_size and find the unwritten
extents first and read zeros instead of actual data, if the direct
writer also takes a shared iolock.
Fix it by updating the in-core inode size after the unwritten extent
conversion. To do this, introduce a new boolean argument to
xfs_iomap_write_unwritten() to tell if we want to update in-core
i_size or not.
Suggested-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Eryu Guan <eguan@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Executing xfs/104 test in a loop on Linux-v4.13 kernel on a ppc64
machine can cause the following NULL pointer dereference,
.queue_work_on+0x4c/0x80
.iomap_dio_bio_end_io+0xbc/0x1f0
.bio_endio+0x118/0x1f0
.blk_update_request+0xd0/0x470
.blk_mq_end_request+0x24/0xc0
.lo_complete_rq+0x40/0xe0
.__blk_mq_complete_request_remote+0x28/0x40
.flush_smp_call_function_queue+0xc4/0x1e0
.smp_ipi_demux_relaxed+0x8c/0x100
.icp_hv_ipi_action+0x54/0xa0
.__handle_irq_event_percpu+0x84/0x2c0
.handle_irq_event_percpu+0x28/0x80
.handle_percpu_irq+0x78/0xc0
.generic_handle_irq+0x40/0x70
.__do_irq+0x88/0x200
.call_do_irq+0x14/0x24
.do_IRQ+0x84/0x130
This occurs due to the following sequence of events,
1. Allocate dio for Direct I/O write.
2. Invoke iomap_apply() until iov_iter_count() bytes have been submitted.
- Assume that we have submitted atleast one bio. Hence iomap_dio->ref value
will be >= 2.
- If during the second iteration, iomap_apply() ends up returning -ENOSPC, we would
break out of the loop and since the 'ret' value is a negative number we
end up not allocating memory for super_block->s_dio_done_wq.
3. Meanwhile, iomap_dio_bio_end_io() is invoked for bios that have been
submitted and here the code ends up dereferencing the NULL pointer stored
at super_block->s_dio_done_wq.
This commit fixes the bug by allocating memory for
super_block->s_dio_done_wq before iomap_apply() is invoked.
Reported-by: Eryu Guan <eguan@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Tested-by: Eryu Guan <eguan@redhat.com>
Signed-off-by: Chandan Rajendra <chandan@linux.vnet.ibm.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Currently only the blocksize is checked, but we should really be calling
bdev_dax_supported() which also tests to make sure we can get a
struct dax_device and that the dax_direct_access() path is working.
This is the same check that we do for the "-o dax" mount option in
xfs_fs_fill_super().
This does not fix the race issues that caused the XFS DAX inode option to
be disabled, so that option will still be disabled. If/when we re-enable
it, though, I think we will want this issue to have been fixed. I also do
think that we want to fix this in stable kernels.
Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com>
CC: stable@vger.kernel.org
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Amir reported a bug discovered by his cleaned up version of my
dm-log-writes xfstests where we were missing csums at certain replay
points. This is because fsx was doing an msync(), which essentially
fsync()'s a specific range of a file. We will log all modified extents,
but only search for the checksums in the range we are being asked to
sync. We cannot simply log the extents in the range we're being asked
because we are logging the inode item as it is currently, which if it
has had a i_size update before the msync means we will miss extents when
replaying. We could possibly get around this by marking the inode with
the transaction that extended the i_size to see if we have this case,
but this would be racy and we'd have to lock the whole range of the
inode to make sure we didn't have an ordered extent outside of our range
that was in the middle of completing.
Fix this simply by keeping track of the modified extents range and
logging the csums for the entire range of extents that we are logging.
This makes the xfstest pass.
Reported-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
commit 4246a0b63b ("block: add a bi_error field to struct bio")
changed the logic of how dio read endio reports errors.
For single stripe dio read, %bio->bi_status reflects the error before
verifying checksum, and now we're updating it when data block matches
with its checksum, while in the mismatching case, %bio->bi_status is
not updated to relfect that.
When some blocks in a file have been corrupted on disk, reading such a
file ends up with
1) checksum errors are reported in kernel log
2) read(2) returns successfully with some content being 0x01.
In order to fix it, we need to report its checksum mismatch error to
the upper layer (dio layer in this case) as well.
Fixes: 4246a0b63b ("block: add a bi_error field to struct bio")
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reported-by: Goffredo Baroncelli <kreijack@inwind.it>
Tested-by: Goffredo Baroncelli <kreijack@inwind.it>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Previously, we were calling del_qgroup_item, and ignoring the return code
resulting in a potential to have divergent in-memory state without an
error. Perhaps, it makes sense to handle this error code, and put the
filesystem into a read only, or similar state.
This patch only adds reporting of the error if the error is fatal,
(any error other than qgroup not found).
Signed-off-by: Sargun Dhillon <sargun@sargun.me>
Reviewed-by: Qu Wenruo <quwenruo.btrfs@gmx.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Currently even if the underlying disk reports failure on IO,
compressed read endio still gets to verify checksum and reports it as
a checksum error.
In fact, if some IO have failed during reading a compressed data
extent , there's no way the checksum could match, therefore, we can
skip that in order to return error quickly to the upper layer.
Please note that we need to do this after recording the failed mirror
index so that read-repair in the upper layer's endio can work
properly.
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Tested-by: Paul Jones <paul@pauljones.id.au>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The kernel oops happens at
kernel BUG at fs/btrfs/extent_io.c:2104!
...
RIP: clean_io_failure+0x263/0x2a0 [btrfs]
It's showing that read-repair code is using an improper mirror index.
This is due to the fact that compression read's endio hasn't recorded
the failed mirror index in %cb->orig_bio.
With this, btrfs's read-repair can work properly on reading compressed
data.
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reported-by: Paul Jones <paul@pauljones.id.au>
Tested-by: Paul Jones <paul@pauljones.id.au>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This seems to be a leftover of commit cf8cddd38b ("btrfs: don't
abuse REQ_OP_* flags for btrfs_map_block").
It should use btrfs_op() helper to provide one of 'enum btrfs_map_op'
types.
Fixes: cf8cddd38b ("btrfs: don't abuse REQ_OP_* flags for btrfs_map_block")
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: Satoru Takeuchi <satoru.takeuchi@gmail.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
It doesn't make sense to backup tree roots when doing fsync, since
during fsync those tree roots have not been consistent on disk.
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: Qu Wenruo <quwenruo.btrfs@gmx.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Currently, "btrfs quota enable" would fail after "btrfs quota disable" on
the first time with syslog output "qgroup_rescan_init failed with -22", but
it would succeed on the second time.
When "quota disable" is called, BTRFS_FS_QUOTA_DISABLING flag bit will be
set in fs_info->flags in btrfs_quota_disable(), but it will not be droppd
in btrfs_run_qgroups() (which is called in btrfs_commit_transaction())
because quota_root has already been freed. If "quota enable" is called
after that, both BTRFS_FS_QUOTA_DISABLING and BTRFS_FS_QUOTA_ENABLED flag
would be dropped in the btrfs_run_qgroups() since quota_root is not NULL.
This leads to the failure of "quota enable" on the first time.
BTRFS_FS_QUOTA_DISABLING flag is not used outside of "quota disable"
context and is equivalent to whether quota_root is NULL or not.
btrfs_run_qgroups() checks whether quota_root is NULL or not in the first
place.
So, let's remove BTRFS_FS_QUOTA_DISABLING flag.
Signed-off-by: Tomohiro Misono <misono.tomohiro@jp.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
btrfs_cmp_data_prepare() (almost) always returns 0 i.e. ignoring errors
from gather_extent_pages(). While the pages are freed by
btrfs_cmp_data_free(), cmp->num_pages still has > 0. Then,
btrfs_extent_same() try to access the already freed pages causing faults
(or violates PageLocked assertion).
This patch just return the error as is so that the caller stop the process.
Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
Fixes: f441460202 ("btrfs: fix deadlock with extent-same and readpage")
Cc: <stable@vger.kernel.org> # 4.2
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
`btrfs sub set-default` succeeds to set an ID which isn't corresponding to any
fs/file tree. If such the bad ID is set to a filesystem, we can't mount this
filesystem without specifying `subvol` or `subvolid` mount options.
Fixes: 6ef5ed0d38 ("Btrfs: add ioctl and incompat flag to set the default mount subvol")
Cc: <stable@vger.kernel.org>
Signed-off-by: Satoru Takeuchi <satoru.takeuchi@gmail.com>
Reviewed-by: Qu Wenruo <quwenruo.btrfs@gmx.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
ENOTSUPP should not be returned to the user program.
(cf. include/linux/errno.h)
Therefore, EOPNOTSUPP is used instead of ENOTSUPP.
Signed-off-by: Tsutomu Itoh <t-itoh@jp.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
__del_reloc_root should be called before freeing up reloc_root->node.
If not, calling __del_reloc_root() dereference reloc_root->node, causing
the system BUG.
Fixes: 6bdf131fac ("Btrfs: don't leak reloc root nodes on error")
Cc: <stable@vger.kernel.org> # 4.9
Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
__endio_write_update_ordered() repeats the search until it reaches the end
of the specified range. This works well with direct IO path, because before
the function is called, it's ensured that there are ordered extents filling
whole the range. It's not the case, however, when it's called from
run_delalloc_range(): it is possible to have error in the midle of the loop
in e.g. run_delalloc_nocow(), so that there exisits the range not covered
by any ordered extents. By cleaning such "uncomplete" range,
__endio_write_update_ordered() stucks at offset where there're no ordered
extents.
Since the ordered extents are created from head to tail, we can stop the
search if there are no offset progress.
Fixes: 524272607e ("btrfs: Handle delalloc error correctly to avoid ordered extent hang")
Cc: <stable@vger.kernel.org> # 4.12
Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
Reviewed-by: Qu Wenruo <quwenruo.btrfs@gmx.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Commit 524272607e ("btrfs: Handle delalloc error correctly to avoid
ordered extent hang") introduced btrfs_cleanup_ordered_extents() to cleanup
submitted ordered extents. However, it does not clear the ordered bit
(Private2) of corresponding pages. Thus, the following BUG occurs from
free_pages_check_bad() (on btrfs/125 with nospace_cache).
BUG: Bad page state in process btrfs pfn:3fa787
page:ffffdf2acfe9e1c0 count:0 mapcount:0 mapping: (null) index:0xd
flags: 0x8000000000002008(uptodate|private_2)
raw: 8000000000002008 0000000000000000 000000000000000d 00000000ffffffff
raw: ffffdf2acf5c1b20 ffffb443802238b0 0000000000000000 0000000000000000
page dumped because: PAGE_FLAGS_CHECK_AT_FREE flag(s) set
bad because of flags: 0x2000(private_2)
This patch clears the flag same as other places calling
btrfs_dec_test_ordered_pending() for every page in the specified range.
Fixes: 524272607e ("btrfs: Handle delalloc error correctly to avoid ordered extent hang")
Cc: <stable@vger.kernel.org> # 4.12
Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
Reviewed-by: Qu Wenruo <quwenruo.btrfs@gmx.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
fs_info->super_copy->{node,sector}size are little-endian, but the ioctl
should return the values in native endianness. Use the cached values in
btrfs_fs_info instead. Found with sparse.
Fixes: 80a773fbfc ("btrfs: retrieve more info from FS_INFO ioctl")
Signed-off-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
flush_epd_write_bio() sets bio->bi_opf by itself to honor REQ_SYNC,
but it's not needed at all since bio->bi_opf has set up properly in
both __extent_writepage() and write_one_eb(), and in the case of
write_one_eb(), it also sets REQ_META, which we will lose in
flush_epd_write_bio().
This remove this unnecessary bio->bi_opf setting.
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This updates btrfs to use the helper wbc_to_write_flags which has been
applied in ext4/xfs/f2fs/block.
Please note that, with this, btrfs's dirty pages written by a
writeback job will carry the flag REQ_BACKGROUND, which is currently
used by writeback-throttle to determine whether it should go to get a
request or wait.
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The TRACE_INCLUDE_FILE macro needs to specify the path relative to the
define_trace.h header rather than relative to the file defining it.
Reported-by: Dmitry Osipenko <digetx@gmail.com>
Tested-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20170823171326.23620-1-thierry.reding@gmail.com
This is in preparation to verify the full xstate header as supplied by user-space.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Eric Biggers <ebiggers3@gmail.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Kevin Hao <haokexin@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Michael Halcrow <mhalcrow@google.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Wanpeng Li <wanpeng.li@hotmail.com>
Cc: Yu-cheng Yu <yu-cheng.yu@intel.com>
Cc: kernel-hardening@lists.openwall.com
Link: http://lkml.kernel.org/r/20170924105913.9157-8-mingo@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This is in preparation to verify the full xstate header as supplied by user-space.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Eric Biggers <ebiggers3@gmail.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Kevin Hao <haokexin@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Michael Halcrow <mhalcrow@google.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Wanpeng Li <wanpeng.li@hotmail.com>
Cc: Yu-cheng Yu <yu-cheng.yu@intel.com>
Cc: kernel-hardening@lists.openwall.com
Link: http://lkml.kernel.org/r/20170924105913.9157-5-mingo@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Move validation of user-supplied xstate_header into a helper function,
in preparation of calling it from both the ptrace and sigreturn syscall
paths.
The new function also considers it to be an error if *any* reserved bits
are set, whereas before we were just clearing most of them silently.
This should reduce the chance of bugs that fail to correctly validate
user-supplied XSAVE areas. It also will expose any broken userspace
programs that set the other reserved bits; this is desirable because
such programs will lose compatibility with future CPUs and kernels if
those bits are ever used for anything. (There shouldn't be any such
programs, and in fact in the case where the compacted format is in use
we were already validating xfeatures. But you never know...)
Signed-off-by: Eric Biggers <ebiggers@google.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Eric Biggers <ebiggers3@gmail.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Kevin Hao <haokexin@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Michael Halcrow <mhalcrow@google.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Wanpeng Li <wanpeng.li@hotmail.com>
Cc: Yu-cheng Yu <yu-cheng.yu@intel.com>
Cc: kernel-hardening@lists.openwall.com
Link: http://lkml.kernel.org/r/20170924105913.9157-2-mingo@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
As per the new nomenclature we don't 'activate' the FPU state
anymore, we initialize it. So drop the _activate_fpstate name
from these functions, which were a bit of a mouthful anyway,
and name them:
fpu__prepare_read()
fpu__prepare_write()
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Eric Biggers <ebiggers3@gmail.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Rename this function to better express that it's all about
initializing the FPU state of a task which goes hand in hand
with the fpu::initialized field.
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Eric Biggers <ebiggers3@gmail.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Yu-cheng Yu <yu-cheng.yu@intel.com>
Link: http://lkml.kernel.org/r/20170923130016.21448-33-mingo@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
fpu__copy() has a preempt_disable()/enable() pair, which it had to do to
be able to atomically unlazy the current task when doing an FNSAVE.
But we don't unlazy tasks anymore, we always do direct saves/restores of
FPU context.
So remove both the unnecessary critical section, and update the comments.
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Eric Biggers <ebiggers3@gmail.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Yu-cheng Yu <yu-cheng.yu@intel.com>
Link: http://lkml.kernel.org/r/20170923130016.21448-32-mingo@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
We don't do any lazy restore anymore, what we have are two pieces of optimization:
- no-FPU tasks that don't save/restore the FPU context (kernel threads are such)
- cached FPU registers maintained via the fpu->last_cpu field. This means that
if an FPU task context switches to a non-FPU task then we can maintain the
FPU registers as an in-FPU copies (cache), and skip the restoration of them
once we switch back to the original FPU-using task.
Update all the comments that still referred to old 'lazy' and 'unlazy' concepts.
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Eric Biggers <ebiggers3@gmail.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Yu-cheng Yu <yu-cheng.yu@intel.com>
Link: http://lkml.kernel.org/r/20170923130016.21448-31-mingo@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The x86 FPU code used to have a complex state machine where both the FPU
registers and the FPU state context could be 'active' (or inactive)
independently of each other - which enabled features like lazy FPU restore.
Much of this complexity is gone in the current code: now we basically can
have FPU-less tasks (kernel threads) that don't use (and save/restore) FPU
state at all, plus full FPU users that save/restore directly with no laziness
whatsoever.
But the fpu::fpstate_active still carries bits of the old complexity - meanwhile
this flag has become a simple flag that shows whether the FPU context saving
area in the thread struct is initialized and used, or not.
Rename it to fpu::initialized to express this simplicity in the name as well.
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Eric Biggers <ebiggers3@gmail.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Yu-cheng Yu <yu-cheng.yu@intel.com>
Link: http://lkml.kernel.org/r/20170923130016.21448-30-mingo@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
fpu__activate_fpstate_read() can be called for the current task
when coredumping - or for stopped tasks when ptrace-ing.
Implement this properly in the code and update the comments.
This also fixes an incorrect (but harmless) warning introduced by
one of the earlier patches.
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Eric Biggers <ebiggers3@gmail.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Yu-cheng Yu <yu-cheng.yu@intel.com>
Link: http://lkml.kernel.org/r/20170923130016.21448-28-mingo@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
